fix(create): exclude better-auth demo integration files when demo is disabled

The better-auth header-user components reference the /demo/better-auth route,
which doesn't exist when users opt out of demo files. Convert these to EJS
templates with conditional rendering so they return null instead of linking
to a non-existent route. Also extend isDemoFilePath filtering to cover
add-on integration files (previously only routes, lib, hooks, data, and
components were filtered in a037c4d).

Author: WaryaWayne

packages/create/src/create-app.ts

@@ -29,8 +29,8 @@ function isDemoFilePath(path?: string) {
     normalized.includes('/lib/demo.') ||
     normalized.includes('/hooks/demo-') ||
     normalized.includes('/hooks/demo.') ||
-    normalized.includes('/data/demo.') ||
     normalized.includes('/data/demo-') ||
+    normalized.includes('/data/demo.') ||
     normalized.includes('/components/demo-') ||
     normalized.includes('/components/demo.')
   )
@@ -49,10 +49,15 @@ function stripExamplesFromOptions(options: Options): Options {
           !isDemoFilePath(route.path) &&
           !(route.url && route.url.startsWith('/demo')),
       )
+      
+      const filteredIntegrations = (addOn.integrations || []).filter(
+        (integration) => !isDemoFilePath(integration.path)
+      )
 
       return {
         ...addOn,
         routes: filteredRoutes,
+        integrations: filteredIntegrations,
         getFiles: async () => {
           const files = await addOn.getFiles()
           return files.filter((file) => !isDemoFilePath(file))

…integrations/better-auth/header-user.tsx …grations/better-auth/header-user.tsx.ejspackages/create/src/frameworks/react/add-ons/better-auth/assets/src/integrations/better-auth/header-user.tsx renamed to packages/create/src/frameworks/react/add-ons/better-auth/assets/src/integrations/better-auth/header-user.tsx.ejs packages/create/src/frameworks/react/add-ons/better-auth/assets/src/integrations/better-auth/header-user.tsx renamed to packages/create/src/frameworks/react/add-ons/better-auth/assets/src/integrations/better-auth/header-user.tsx.ejs

@@ -1,5 +1,7 @@
 import { authClient } from "#/lib/auth-client";
+<%_ if (routes.some(r => r.url === '/demo/better-auth')) { _%>
 import { Link } from "@tanstack/react-router";
+<%_ } _%>
 
 export default function BetterAuthHeader() {
   const { data: session, isPending } = authClient.useSession();
@@ -34,6 +36,7 @@ export default function BetterAuthHeader() {
     );
   }
 
+<%_ if (routes.some(r => r.url === '/demo/better-auth')) { _%>
   return (
     <Link
       to="/demo/better-auth"
@@ -42,4 +45,7 @@ export default function BetterAuthHeader() {
       Sign in
     </Link>
   );
+<%_ } else { _%>
+  return null;
+<%_ } _%>
 }

…integrations/better-auth/header-user.tsx …grations/better-auth/header-user.tsx.ejspackages/create/src/frameworks/solid/add-ons/better-auth/assets/src/integrations/better-auth/header-user.tsx renamed to packages/create/src/frameworks/solid/add-ons/better-auth/assets/src/integrations/better-auth/header-user.tsx.ejs packages/create/src/frameworks/solid/add-ons/better-auth/assets/src/integrations/better-auth/header-user.tsx renamed to packages/create/src/frameworks/solid/add-ons/better-auth/assets/src/integrations/better-auth/header-user.tsx.ejs

@@ -1,5 +1,7 @@
 import { Show } from "solid-js";
+<%_ if (routes.some(r => r.url === '/demo/better-auth')) { _%>
 import { Link } from "@tanstack/solid-router";
+<%_ } _%>
 import { authClient } from "../../lib/auth-client";
 
 export default function BetterAuthHeader() {
@@ -14,6 +16,7 @@ export default function BetterAuthHeader() {
     >
       <Show
         when={session().data?.user}
+<%_ if (routes.some(r => r.url === '/demo/better-auth')) { _%>
         fallback={
           <Link
             to="/demo/better-auth"
@@ -22,6 +25,7 @@ export default function BetterAuthHeader() {
             Sign in
           </Link>
         }
+<%_ } _%>
       >
         {(user) => (
           <div class="flex items-center gap-2">